docs: def get_mean_and_stddevs(self, sites, rup, dists, imt, stddev_types):
          """
          See :meth:`superclass method
          <.base.GroundShakingIntensityModel.get_mean_and_stddevs>`
          for spec of input and result values.
          """
          R = (dists.rrup)
          M = rup.mag
          # get constants
          Ssr = self.get_Ssr_term(sites.vs30)
          Shr = self.get_Shr_term(sites.vs30)
          rake = rup.rake
          F = self.get_fault_term(rake)
  
          # compute mean
          mean = -3.512 + (0.904 * M) - (1.328 * np.log(np.sqrt(R**2
                 + (0.149 * np.exp(0.647 * M))**2))) \
                 + (1.125 - 0.112 * np.log(R) - 0.0957 * M) * F \
                 + (0.440 - 0.171 * np.log(R)) * Ssr \
                 + (0.405 - 0.222 * np.log(R)) * Shr
          stddevs = self.get_stddevs(mean, stddev_types)
          return mean, stddevs